Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]
FreeBSD/Linux Kernel Cross Reference
sys/netinet/tcp_subr.c
Version:
- FREEBSD - FREEBSD-13-STABLE - FREEBSD-13-0 - FREEBSD-12-STABLE - FREEBSD-12-0 - FREEBSD-11-STABLE - FREEBSD-11-0 - FREEBSD-10-STABLE - FREEBSD-10-0 - FREEBSD-9-STABLE - FREEBSD-9-0 - FREEBSD-8-STABLE - FREEBSD-8-0 - FREEBSD-7-STABLE - FREEBSD-7-0 - FREEBSD-6-STABLE - FREEBSD-6-0 - FREEBSD-5-STABLE - FREEBSD-5-0 - FREEBSD-4-STABLE - FREEBSD-3-STABLE - FREEBSD22 - l41 - OPENBSD - linux-2.6 - MK84 - PLAN9 - xnu-8792
SearchContext: - none - 3 - 10
SearchContext: - none - 3 - 10
1 /*- 2 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)tcp_subr.c 8.2 (Berkeley) 5/24/95 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD: releng/8.1/sys/netinet/tcp_subr.c 207695 2010-05-06 06:44:19Z bz $"); 34 35 #include "opt_compat.h" 36 #include "opt_inet.h" 37 #include "opt_inet6.h" 38 #include "opt_ipsec.h" 39 #include "opt_tcpdebug.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/callout.h> 44 #include <sys/kernel.h> 45 #include <sys/sysctl.h> 46 #include <sys/jail.h> 47 #include <sys/malloc.h> 48 #include <sys/mbuf.h> 49 #ifdef INET6 50 #include <sys/domain.h> 51 #endif 52 #include <sys/priv.h> 53 #include <sys/proc.h> 54 #include <sys/socket.h> 55 #include <sys/socketvar.h> 56 #include <sys/protosw.h> 57 #include <sys/random.h> 58 59 #include <vm/uma.h> 60 61 #include <net/route.h> 62 #include <net/if.h> 63 #include <net/vnet.h> 64 65 #include <netinet/in.h> 66 #include <netinet/in_systm.h> 67 #include <netinet/ip.h> 68 #ifdef INET6 69 #include <netinet/ip6.h> 70 #endif 71 #include <netinet/in_pcb.h> 72 #ifdef INET6 73 #include <netinet6/in6_pcb.h> 74 #endif 75 #include <netinet/in_var.h> 76 #include <netinet/ip_var.h> 77 #ifdef INET6 78 #include <netinet6/ip6_var.h> 79 #include <netinet6/scope6_var.h> 80 #include <netinet6/nd6.h> 81 #endif 82 #include <netinet/ip_icmp.h> 83 #include <netinet/tcp.h> 84 #include <netinet/tcp_fsm.h> 85 #include <netinet/tcp_seq.h> 86 #include <netinet/tcp_timer.h> 87 #include <netinet/tcp_var.h> 88 #include <netinet/tcp_syncache.h> 89 #include <netinet/tcp_offload.h> 90 #ifdef INET6 91 #include <netinet6/tcp6_var.h> 92 #endif 93 #include <netinet/tcpip.h> 94 #ifdef TCPDEBUG 95 #include <netinet/tcp_debug.h> 96 #endif 97 #include <netinet6/ip6protosw.h> 98 99 #ifdef IPSEC 100 #include <netipsec/ipsec.h> 101 #include <netipsec/xform.h> 102 #ifdef INET6 103 #include <netipsec/ipsec6.h> 104 #endif 105 #include <netipsec/key.h> 106 #include <sys/syslog.h> 107 #endif /*IPSEC*/ 108 109 #include <machine/in_cksum.h> 110 #include <sys/md5.h> 111 112 #include <security/mac/mac_framework.h> 113 114 VNET_DEFINE(int, tcp_mssdflt) = TCP_MSS; 115 #ifdef INET6 116 VNET_DEFINE(int, tcp_v6mssdflt) = TCP6_MSS; 117 #endif 118 119 static int 120 sysctl_net_inet_tcp_mss_check(SYSCTL_HANDLER_ARGS) 121 { 122 int error, new; 123 124 new = V_tcp_mssdflt; 125 error = sysctl_handle_int(oidp, &new, 0, req); 126 if (error == 0 && req->newptr) { 127 if (new < TCP_MINMSS) 128 error = EINVAL; 129 else 130 V_tcp_mssdflt = new; 131 } 132 return (error); 133 } 134 135 SYSCTL_VNET_PROC(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt, 136 CTLTYPE_INT|CTLFLAG_RW, &VNET_NAME(tcp_mssdflt), 0, 137 &sysctl_net_inet_tcp_mss_check, "I", 138 "Default TCP Maximum Segment Size"); 139 140 #ifdef INET6 141 static int 142 sysctl_net_inet_tcp_mss_v6_check(SYSCTL_HANDLER_ARGS) 143 { 144 int error, new; 145 146 new = V_tcp_v6mssdflt; 147 error = sysctl_handle_int(oidp, &new, 0, req); 148 if (error == 0 && req->newptr) { 149 if (new < TCP_MINMSS) 150 error = EINVAL; 151 else 152 V_tcp_v6mssdflt = new; 153 } 154 return (error); 155 } 156 157 SYSCTL_VNET_PROC(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt, 158 CTLTYPE_INT|CTLFLAG_RW, &VNET_NAME(tcp_v6mssdflt), 0, 159 &sysctl_net_inet_tcp_mss_v6_check, "I", 160 "Default TCP Maximum Segment Size for IPv6"); 161 #endif 162 163 static int 164 vnet_sysctl_msec_to_ticks(SYSCTL_HANDLER_ARGS) 165 { 166 167 VNET_SYSCTL_ARG(req, arg1); 168 return (sysctl_msec_to_ticks(oidp, arg1, arg2, req)); 169 } 170 171 /* 172 * Minimum MSS we accept and use. This prevents DoS attacks where 173 * we are forced to a ridiculous low MSS like 20 and send hundreds 174 * of packets instead of one. The effect scales with the available 175 * bandwidth and quickly saturates the CPU and network interface 176 * with packet generation and sending. Set to zero to disable MINMSS 177 * checking. This setting prevents us from sending too small packets. 178 */ 179 VNET_DEFINE(int, tcp_minmss) = TCP_MINMSS; 180 SYSCTL_VNET_INT(_net_inet_tcp, OID_AUTO, minmss, CTLFLAG_RW, 181 &VNET_NAME(tcp_minmss), 0, 182 "Minmum TCP Maximum Segment Size"); 183 184 VNET_DEFINE(int, tcp_do_rfc1323) = 1; 185 SYSCTL_VNET_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_RW, 186 &VNET_NAME(tcp_do_rfc1323), 0, 187 "Enable rfc1323 (high performance TCP) extensions"); 188 189 static int tcp_log_debug = 0; 190 SYSCTL_INT(_net_inet_tcp, OID_AUTO, log_debug, CTLFLAG_RW, 191 &tcp_log_debug, 0, "Log errors caused by incoming TCP segments"); 192 193 static int tcp_tcbhashsize = 0; 194 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RDTUN, 195 &tcp_tcbhashsize, 0, "Size of TCP control-block hashtable"); 196 197 static int do_tcpdrain = 1; 198 SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0, 199 "Enable tcp_drain routine for extra help when low on mbufs"); 200 201 SYSCTL_VNET_INT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_RD, 202 &VNET_NAME(tcbinfo.ipi_count), 0, "Number of active PCBs"); 203 204 static VNET_DEFINE(int, icmp_may_rst) = 1; 205 #define V_icmp_may_rst VNET(icmp_may_rst) 206 SYSCTL_VNET_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_RW, 207 &VNET_NAME(icmp_may_rst), 0, 208 "Certain ICMP unreachable messages may abort connections in SYN_SENT"); 209 210 static VNET_DEFINE(int, tcp_isn_reseed_interval) = 0; 211 #define V_tcp_isn_reseed_interval VNET(tcp_isn_reseed_interval) 212 SYSCTL_VNET_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_RW, 213 &VNET_NAME(tcp_isn_reseed_interval), 0, 214 "Seconds between reseeding of ISN secret"); 215 216 /* 217 * TCP bandwidth limiting sysctls. Note that the default lower bound of 218 * 1024 exists only for debugging. A good production default would be 219 * something like 6100. 220 */ 221 SYSCTL_NODE(_net_inet_tcp, OID_AUTO, inflight, CTLFLAG_RW, 0, 222 "TCP inflight data limiting"); 223 224 static VNET_DEFINE(int, tcp_inflight_enable) = 1; 225 #define V_tcp_inflight_enable VNET(tcp_inflight_enable) 226 SYSCTL_VNET_INT(_net_inet_tcp_inflight, OID_AUTO, enable, CTLFLAG_RW, 227 &VNET_NAME(tcp_inflight_enable), 0, 228 "Enable automatic TCP inflight data limiting"); 229 230 static int tcp_inflight_debug = 0; 231 SYSCTL_INT(_net_inet_tcp_inflight, OID_AUTO, debug, CTLFLAG_RW, 232 &tcp_inflight_debug, 0, 233 "Debug TCP inflight calculations"); 234 235 static VNET_DEFINE(int, tcp_inflight_rttthresh); 236 #define V_tcp_inflight_rttthresh VNET(tcp_inflight_rttthresh) 237 SYSCTL_VNET_PROC(_net_inet_tcp_inflight, OID_AUTO, rttthresh, 238 CTLTYPE_INT|CTLFLAG_RW, &VNET_NAME(tcp_inflight_rttthresh), 0, 239 vnet_sysctl_msec_to_ticks, "I", 240 "RTT threshold below which inflight will deactivate itself"); 241 242 static VNET_DEFINE(int, tcp_inflight_min) = 6144; 243 #define V_tcp_inflight_min VNET(tcp_inflight_min) 244 SYSCTL_VNET_INT(_net_inet_tcp_inflight, OID_AUTO, min, CTLFLAG_RW, 245 &VNET_NAME(tcp_inflight_min), 0, 246 "Lower-bound for TCP inflight window"); 247 248 static VNET_DEFINE(int, tcp_inflight_max) = TCP_MAXWIN << TCP_MAX_WINSHIFT; 249 #define V_tcp_inflight_max VNET(tcp_inflight_max) 250 SYSCTL_VNET_INT(_net_inet_tcp_inflight, OID_AUTO, max, CTLFLAG_RW, 251 &VNET_NAME(tcp_inflight_max), 0, 252 "Upper-bound for TCP inflight window"); 253 254 static VNET_DEFINE(int, tcp_inflight_stab) = 20; 255 #define V_tcp_inflight_stab VNET(tcp_inflight_stab) 256 SYSCTL_VNET_INT(_net_inet_tcp_inflight, OID_AUTO, stab, CTLFLAG_RW, 257 &VNET_NAME(tcp_inflight_stab), 0, 258 "Inflight Algorithm Stabilization 20 = 2 packets"); 259 260 VNET_DEFINE(uma_zone_t, sack_hole_zone); 261 #define V_sack_hole_zone VNET(sack_hole_zone) 262 263 static struct inpcb *tcp_notify(struct inpcb *, int); 264 static void tcp_isn_tick(void *); 265 266 /* 267 * Target size of TCP PCB hash tables. Must be a power of two. 268 * 269 * Note that this can be overridden by the kernel environment 270 * variable net.inet.tcp.tcbhashsize 271 */ 272 #ifndef TCBHASHSIZE 273 #define TCBHASHSIZE 512 274 #endif 275 276 /* 277 * XXX 278 * Callouts should be moved into struct tcp directly. They are currently 279 * separate because the tcpcb structure is exported to userland for sysctl 280 * parsing purposes, which do not know about callouts. 281 */ 282 struct tcpcb_mem { 283 struct tcpcb tcb; 284 struct tcp_timer tt; 285 }; 286 287 static VNET_DEFINE(uma_zone_t, tcpcb_zone); 288 #define V_tcpcb_zone VNET(tcpcb_zone) 289 290 MALLOC_DEFINE(M_TCPLOG, "tcplog", "TCP address and flags print buffers"); 291 struct callout isn_callout; 292 static struct mtx isn_mtx; 293 294 #define ISN_LOCK_INIT() mtx_init(&isn_mtx, "isn_mtx", NULL, MTX_DEF) 295 #define ISN_LOCK() mtx_lock(&isn_mtx) 296 #define ISN_UNLOCK() mtx_unlock(&isn_mtx) 297 298 /* 299 * TCP initialization. 300 */ 301 static void 302 tcp_zone_change(void *tag) 303 { 304 305 uma_zone_set_max(V_tcbinfo.ipi_zone, maxsockets); 306 uma_zone_set_max(V_tcpcb_zone, maxsockets); 307 tcp_tw_zone_change(); 308 } 309 310 static int 311 tcp_inpcb_init(void *mem, int size, int flags) 312 { 313 struct inpcb *inp = mem; 314 315 INP_LOCK_INIT(inp, "inp", "tcpinp"); 316 return (0); 317 } 318 319 void 320 tcp_init(void) 321 { 322 int hashsize; 323 324 INP_INFO_LOCK_INIT(&V_tcbinfo, "tcp"); 325 LIST_INIT(&V_tcb); 326 #ifdef VIMAGE 327 V_tcbinfo.ipi_vnet = curvnet; 328 #endif 329 V_tcbinfo.ipi_listhead = &V_tcb; 330 hashsize = TCBHASHSIZE; 331 TUNABLE_INT_FETCH("net.inet.tcp.tcbhashsize", &hashsize); 332 if (!powerof2(hashsize)) { 333 printf("WARNING: TCB hash size not a power of 2\n"); 334 hashsize = 512; /* safe default */ 335 } 336 V_tcbinfo.ipi_hashbase = hashinit(hashsize, M_PCB, 337 &V_tcbinfo.ipi_hashmask); 338 V_tcbinfo.ipi_porthashbase = hashinit(hashsize, M_PCB, 339 &V_tcbinfo.ipi_porthashmask); 340 V_tcbinfo.ipi_zone = uma_zcreate("tcp_inpcb", sizeof(struct inpcb), 341 NULL, NULL, tcp_inpcb_init, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 342 uma_zone_set_max(V_tcbinfo.ipi_zone, maxsockets); 343 V_tcp_inflight_rttthresh = TCPTV_INFLIGHT_RTTTHRESH; 344 345 /* 346 * These have to be type stable for the benefit of the timers. 347 */ 348 V_tcpcb_zone = uma_zcreate("tcpcb", sizeof(struct tcpcb_mem), 349 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 350 uma_zone_set_max(V_tcpcb_zone, maxsockets); 351 352 tcp_tw_init(); 353 syncache_init(); 354 tcp_hc_init(); 355 tcp_reass_init(); 356 357 TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack); 358 V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole), 359 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 360 361 /* Skip initialization of globals for non-default instances. */ 362 if (!IS_DEFAULT_VNET(curvnet)) 363 return; 364 365 /* XXX virtualize those bellow? */ 366 tcp_delacktime = TCPTV_DELACK; 367 tcp_keepinit = TCPTV_KEEP_INIT; 368 tcp_keepidle = TCPTV_KEEP_IDLE; 369 tcp_keepintvl = TCPTV_KEEPINTVL; 370 tcp_maxpersistidle = TCPTV_KEEP_IDLE; 371 tcp_msl = TCPTV_MSL; 372 tcp_rexmit_min = TCPTV_MIN; 373 if (tcp_rexmit_min < 1) 374 tcp_rexmit_min = 1; 375 tcp_rexmit_slop = TCPTV_CPU_VAR; 376 tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT; 377 tcp_tcbhashsize = hashsize; 378 379 #ifdef INET6 380 #define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr)) 381 #else /* INET6 */ 382 #define TCP_MINPROTOHDR (sizeof(struct tcpiphdr)) 383 #endif /* INET6 */ 384 if (max_protohdr < TCP_MINPROTOHDR) 385 max_protohdr = TCP_MINPROTOHDR; 386 if (max_linkhdr + TCP_MINPROTOHDR > MHLEN) 387 panic("tcp_init"); 388 #undef TCP_MINPROTOHDR 389 390 ISN_LOCK_INIT(); 391 callout_init(&isn_callout, CALLOUT_MPSAFE); 392 callout_reset(&isn_callout, hz/100, tcp_isn_tick, NULL); 393 EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL, 394 SHUTDOWN_PRI_DEFAULT); 395 EVENTHANDLER_REGISTER(maxsockets_change, tcp_zone_change, NULL, 396 EVENTHANDLER_PRI_ANY); 397 } 398 399 #ifdef VIMAGE 400 void 401 tcp_destroy(void) 402 { 403 404 tcp_reass_destroy(); 405 tcp_hc_destroy(); 406 syncache_destroy(); 407 tcp_tw_destroy(); 408 409 /* XXX check that hashes are empty! */ 410 hashdestroy(V_tcbinfo.ipi_hashbase, M_PCB, 411 V_tcbinfo.ipi_hashmask); 412 hashdestroy(V_tcbinfo.ipi_porthashbase, M_PCB, 413 V_tcbinfo.ipi_porthashmask); 414 415 uma_zdestroy(V_sack_hole_zone); 416 uma_zdestroy(V_tcpcb_zone); 417 uma_zdestroy(V_tcbinfo.ipi_zone); 418 419 INP_INFO_LOCK_DESTROY(&V_tcbinfo); 420 } 421 #endif 422 423 void 424 tcp_fini(void *xtp) 425 { 426 427 callout_stop(&isn_callout); 428 } 429 430 /* 431 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb. 432 * tcp_template used to store this data in mbufs, but we now recopy it out 433 * of the tcpcb each time to conserve mbufs. 434 */ 435 void 436 tcpip_fillheaders(struct inpcb *inp, void *ip_ptr, void *tcp_ptr) 437 { 438 struct tcphdr *th = (struct tcphdr *)tcp_ptr; 439 440 INP_WLOCK_ASSERT(inp); 441 442 #ifdef INET6 443 if ((inp->inp_vflag & INP_IPV6) != 0) { 444 struct ip6_hdr *ip6; 445 446 ip6 = (struct ip6_hdr *)ip_ptr; 447 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) | 448 (inp->inp_flow & IPV6_FLOWINFO_MASK); 449 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) | 450 (IPV6_VERSION & IPV6_VERSION_MASK); 451 ip6->ip6_nxt = IPPROTO_TCP; 452 ip6->ip6_plen = htons(sizeof(struct tcphdr)); 453 ip6->ip6_src = inp->in6p_laddr; 454 ip6->ip6_dst = inp->in6p_faddr; 455 } else 456 #endif 457 { 458 struct ip *ip; 459 460 ip = (struct ip *)ip_ptr; 461 ip->ip_v = IPVERSION; 462 ip->ip_hl = 5; 463 ip->ip_tos = inp->inp_ip_tos; 464 ip->ip_len = 0; 465 ip->ip_id = 0; 466 ip->ip_off = 0; 467 ip->ip_ttl = inp->inp_ip_ttl; 468 ip->ip_sum = 0; 469 ip->ip_p = IPPROTO_TCP; 470 ip->ip_src = inp->inp_laddr; 471 ip->ip_dst = inp->inp_faddr; 472 } 473 th->th_sport = inp->inp_lport; 474 th->th_dport = inp->inp_fport; 475 th->th_seq = 0; 476 th->th_ack = 0; 477 th->th_x2 = 0; 478 th->th_off = 5; 479 th->th_flags = 0; 480 th->th_win = 0; 481 th->th_urp = 0; 482 th->th_sum = 0; /* in_pseudo() is called later for ipv4 */ 483 } 484 485 /* 486 * Create template to be used to send tcp packets on a connection. 487 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only 488 * use for this function is in keepalives, which use tcp_respond. 489 */ 490 struct tcptemp * 491 tcpip_maketemplate(struct inpcb *inp) 492 { 493 struct tcptemp *t; 494 495 t = malloc(sizeof(*t), M_TEMP, M_NOWAIT); 496 if (t == NULL) 497 return (NULL); 498 tcpip_fillheaders(inp, (void *)&t->tt_ipgen, (void *)&t->tt_t); 499 return (t); 500 } 501 502 /* 503 * Send a single message to the TCP at address specified by 504 * the given TCP/IP header. If m == NULL, then we make a copy 505 * of the tcpiphdr at ti and send directly to the addressed host. 506 * This is used to force keep alive messages out using the TCP 507 * template for a connection. If flags are given then we send 508 * a message back to the TCP which originated the * segment ti, 509 * and discard the mbuf containing it and any other attached mbufs. 510 * 511 * In any case the ack and sequence number of the transmitted 512 * segment are as specified by the parameters. 513 * 514 * NOTE: If m != NULL, then ti must point to *inside* the mbuf. 515 */ 516 void 517 tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m, 518 tcp_seq ack, tcp_seq seq, int flags) 519 { 520 int tlen; 521 int win = 0; 522 struct ip *ip; 523 struct tcphdr *nth; 524 #ifdef INET6 525 struct ip6_hdr *ip6; 526 int isipv6; 527 #endif /* INET6 */ 528 int ipflags = 0; 529 struct inpcb *inp; 530 531 KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL")); 532 533 #ifdef INET6 534 isipv6 = ((struct ip *)ipgen)->ip_v == 6; 535 ip6 = ipgen; 536 #endif /* INET6 */ 537 ip = ipgen; 538 539 if (tp != NULL) { 540 inp = tp->t_inpcb; 541 KASSERT(inp != NULL, ("tcp control block w/o inpcb")); 542 INP_WLOCK_ASSERT(inp); 543 } else 544 inp = NULL; 545 546 if (tp != NULL) { 547 if (!(flags & TH_RST)) { 548 win = sbspace(&inp->inp_socket->so_rcv); 549 if (win > (long)TCP_MAXWIN << tp->rcv_scale) 550 win = (long)TCP_MAXWIN << tp->rcv_scale; 551 } 552 } 553 if (m == NULL) { 554 m = m_gethdr(M_DONTWAIT, MT_DATA); 555 if (m == NULL) 556 return; 557 tlen = 0; 558 m->m_data += max_linkhdr; 559 #ifdef INET6 560 if (isipv6) { 561 bcopy((caddr_t)ip6, mtod(m, caddr_t), 562 sizeof(struct ip6_hdr)); 563 ip6 = mtod(m, struct ip6_hdr *); 564 nth = (struct tcphdr *)(ip6 + 1); 565 } else 566 #endif /* INET6 */ 567 { 568 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 569 ip = mtod(m, struct ip *); 570 nth = (struct tcphdr *)(ip + 1); 571 } 572 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 573 flags = TH_ACK; 574 } else { 575 /* 576 * reuse the mbuf. 577 * XXX MRT We inherrit the FIB, which is lucky. 578 */ 579 m_freem(m->m_next); 580 m->m_next = NULL; 581 m->m_data = (caddr_t)ipgen; 582 /* m_len is set later */ 583 tlen = 0; 584 #define xchg(a,b,type) { type t; t=a; a=b; b=t; } 585 #ifdef INET6 586 if (isipv6) { 587 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 588 nth = (struct tcphdr *)(ip6 + 1); 589 } else 590 #endif /* INET6 */ 591 { 592 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 593 nth = (struct tcphdr *)(ip + 1); 594 } 595 if (th != nth) { 596 /* 597 * this is usually a case when an extension header 598 * exists between the IPv6 header and the 599 * TCP header. 600 */ 601 nth->th_sport = th->th_sport; 602 nth->th_dport = th->th_dport; 603 } 604 xchg(nth->th_dport, nth->th_sport, uint16_t); 605 #undef xchg 606 } 607 #ifdef INET6 608 if (isipv6) { 609 ip6->ip6_flow = 0; 610 ip6->ip6_vfc = IPV6_VERSION; 611 ip6->ip6_nxt = IPPROTO_TCP; 612 ip6->ip6_plen = htons((u_short)(sizeof (struct tcphdr) + 613 tlen)); 614 tlen += sizeof (struct ip6_hdr) + sizeof (struct tcphdr); 615 } else 616 #endif 617 { 618 tlen += sizeof (struct tcpiphdr); 619 ip->ip_len = tlen; 620 ip->ip_ttl = V_ip_defttl; 621 if (V_path_mtu_discovery) 622 ip->ip_off |= IP_DF; 623 } 624 m->m_len = tlen; 625 m->m_pkthdr.len = tlen; 626 m->m_pkthdr.rcvif = NULL; 627 #ifdef MAC 628 if (inp != NULL) { 629 /* 630 * Packet is associated with a socket, so allow the 631 * label of the response to reflect the socket label. 632 */ 633 INP_WLOCK_ASSERT(inp); 634 mac_inpcb_create_mbuf(inp, m); 635 } else { 636 /* 637 * Packet is not associated with a socket, so possibly 638 * update the label in place. 639 */ 640 mac_netinet_tcp_reply(m); 641 } 642 #endif 643 nth->th_seq = htonl(seq); 644 nth->th_ack = htonl(ack); 645 nth->th_x2 = 0; 646 nth->th_off = sizeof (struct tcphdr) >> 2; 647 nth->th_flags = flags; 648 if (tp != NULL) 649 nth->th_win = htons((u_short) (win >> tp->rcv_scale)); 650 else 651 nth->th_win = htons((u_short)win); 652 nth->th_urp = 0; 653 #ifdef INET6 654 if (isipv6) { 655 nth->th_sum = 0; 656 nth->th_sum = in6_cksum(m, IPPROTO_TCP, 657 sizeof(struct ip6_hdr), 658 tlen - sizeof(struct ip6_hdr)); 659 ip6->ip6_hlim = in6_selecthlim(tp != NULL ? tp->t_inpcb : 660 NULL, NULL); 661 } else 662 #endif /* INET6 */ 663 { 664 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 665 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p))); 666 m->m_pkthdr.csum_flags = CSUM_TCP; 667 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 668 } 669 #ifdef TCPDEBUG 670 if (tp == NULL || (inp->inp_socket->so_options & SO_DEBUG)) 671 tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0); 672 #endif 673 #ifdef INET6 674 if (isipv6) 675 (void) ip6_output(m, NULL, NULL, ipflags, NULL, NULL, inp); 676 else 677 #endif /* INET6 */ 678 (void) ip_output(m, NULL, NULL, ipflags, NULL, inp); 679 } 680 681 /* 682 * Create a new TCP control block, making an 683 * empty reassembly queue and hooking it to the argument 684 * protocol control block. The `inp' parameter must have 685 * come from the zone allocator set up in tcp_init(). 686 */ 687 struct tcpcb * 688 tcp_newtcpcb(struct inpcb *inp) 689 { 690 struct tcpcb_mem *tm; 691 struct tcpcb *tp; 692 #ifdef INET6 693 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 694 #endif /* INET6 */ 695 696 tm = uma_zalloc(V_tcpcb_zone, M_NOWAIT | M_ZERO); 697 if (tm == NULL) 698 return (NULL); 699 tp = &tm->tcb; 700 #ifdef VIMAGE 701 tp->t_vnet = inp->inp_vnet; 702 #endif 703 tp->t_timers = &tm->tt; 704 /* LIST_INIT(&tp->t_segq); */ /* XXX covered by M_ZERO */ 705 tp->t_maxseg = tp->t_maxopd = 706 #ifdef INET6 707 isipv6 ? V_tcp_v6mssdflt : 708 #endif /* INET6 */ 709 V_tcp_mssdflt; 710 711 /* Set up our timeouts. */ 712 callout_init(&tp->t_timers->tt_rexmt, CALLOUT_MPSAFE); 713 callout_init(&tp->t_timers->tt_persist, CALLOUT_MPSAFE); 714 callout_init(&tp->t_timers->tt_keep, CALLOUT_MPSAFE); 715 callout_init(&tp->t_timers->tt_2msl, CALLOUT_MPSAFE); 716 callout_init(&tp->t_timers->tt_delack, CALLOUT_MPSAFE); 717 718 if (V_tcp_do_rfc1323) 719 tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP); 720 if (V_tcp_do_sack) 721 tp->t_flags |= TF_SACK_PERMIT; 722 TAILQ_INIT(&tp->snd_holes); 723 tp->t_inpcb = inp; /* XXX */ 724 /* 725 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no 726 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives 727 * reasonable initial retransmit time. 728 */ 729 tp->t_srtt = TCPTV_SRTTBASE; 730 tp->t_rttvar = ((TCPTV_RTOBASE - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; 731 tp->t_rttmin = tcp_rexmit_min; 732 tp->t_rxtcur = TCPTV_RTOBASE; 733 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 734 tp->snd_bwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 735 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; 736 tp->t_rcvtime = ticks; 737 tp->t_bw_rtttime = ticks; 738 /* 739 * IPv4 TTL initialization is necessary for an IPv6 socket as well, 740 * because the socket may be bound to an IPv6 wildcard address, 741 * which may match an IPv4-mapped IPv6 address. 742 */ 743 inp->inp_ip_ttl = V_ip_defttl; 744 inp->inp_ppcb = tp; 745 return (tp); /* XXX */ 746 } 747 748 /* 749 * Drop a TCP connection, reporting 750 * the specified error. If connection is synchronized, 751 * then send a RST to peer. 752 */ 753 struct tcpcb * 754 tcp_drop(struct tcpcb *tp, int errno) 755 { 756 struct socket *so = tp->t_inpcb->inp_socket; 757 758 INP_INFO_WLOCK_ASSERT(&V_tcbinfo); 759 INP_WLOCK_ASSERT(tp->t_inpcb); 760 761 if (TCPS_HAVERCVDSYN(tp->t_state)) { 762 tp->t_state = TCPS_CLOSED; 763 (void) tcp_output_reset(tp); 764 TCPSTAT_INC(tcps_drops); 765 } else 766 TCPSTAT_INC(tcps_conndrops); 767 if (errno == ETIMEDOUT && tp->t_softerror) 768 errno = tp->t_softerror; 769 so->so_error = errno; 770 return (tcp_close(tp)); 771 } 772 773 void 774 tcp_discardcb(struct tcpcb *tp) 775 { 776 struct tseg_qent *q; 777 struct inpcb *inp = tp->t_inpcb; 778 struct socket *so = inp->inp_socket; 779 #ifdef INET6 780 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 781 #endif /* INET6 */ 782 783 INP_WLOCK_ASSERT(inp); 784 785 /* 786 * Make sure that all of our timers are stopped before we 787 * delete the PCB. 788 */ 789 callout_stop(&tp->t_timers->tt_rexmt); 790 callout_stop(&tp->t_timers->tt_persist); 791 callout_stop(&tp->t_timers->tt_keep); 792 callout_stop(&tp->t_timers->tt_2msl); 793 callout_stop(&tp->t_timers->tt_delack); 794 795 /* 796 * If we got enough samples through the srtt filter, 797 * save the rtt and rttvar in the routing entry. 798 * 'Enough' is arbitrarily defined as 4 rtt samples. 799 * 4 samples is enough for the srtt filter to converge 800 * to within enough % of the correct value; fewer samples 801 * and we could save a bogus rtt. The danger is not high 802 * as tcp quickly recovers from everything. 803 * XXX: Works very well but needs some more statistics! 804 */ 805 if (tp->t_rttupdated >= 4) { 806 struct hc_metrics_lite metrics; 807 u_long ssthresh; 808 809 bzero(&metrics, sizeof(metrics)); 810 /* 811 * Update the ssthresh always when the conditions below 812 * are satisfied. This gives us better new start value 813 * for the congestion avoidance for new connections. 814 * ssthresh is only set if packet loss occured on a session. 815 * 816 * XXXRW: 'so' may be NULL here, and/or socket buffer may be 817 * being torn down. Ideally this code would not use 'so'. 818 */ 819 ssthresh = tp->snd_ssthresh; 820 if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) { 821 /* 822 * convert the limit from user data bytes to 823 * packets then to packet data bytes. 824 */ 825 ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg; 826 if (ssthresh < 2) 827 ssthresh = 2; 828 ssthresh *= (u_long)(tp->t_maxseg + 829 #ifdef INET6 830 (isipv6 ? sizeof (struct ip6_hdr) + 831 sizeof (struct tcphdr) : 832 #endif 833 sizeof (struct tcpiphdr) 834 #ifdef INET6 835 ) 836 #endif 837 ); 838 } else 839 ssthresh = 0; 840 metrics.rmx_ssthresh = ssthresh; 841 842 metrics.rmx_rtt = tp->t_srtt; 843 metrics.rmx_rttvar = tp->t_rttvar; 844 /* XXX: This wraps if the pipe is more than 4 Gbit per second */ 845 metrics.rmx_bandwidth = tp->snd_bandwidth; 846 metrics.rmx_cwnd = tp->snd_cwnd; 847 metrics.rmx_sendpipe = 0; 848 metrics.rmx_recvpipe = 0; 849 850 tcp_hc_update(&inp->inp_inc, &metrics); 851 } 852 853 /* free the reassembly queue, if any */ 854 while ((q = LIST_FIRST(&tp->t_segq)) != NULL) { 855 LIST_REMOVE(q, tqe_q); 856 m_freem(q->tqe_m); 857 uma_zfree(V_tcp_reass_zone, q); 858 tp->t_segqlen--; 859 V_tcp_reass_qsize--; 860 } 861 /* Disconnect offload device, if any. */ 862 tcp_offload_detach(tp); 863 864 tcp_free_sackholes(tp); 865 inp->inp_ppcb = NULL; 866 tp->t_inpcb = NULL; 867 uma_zfree(V_tcpcb_zone, tp); 868 } 869 870 /* 871 * Attempt to close a TCP control block, marking it as dropped, and freeing 872 * the socket if we hold the only reference. 873 */ 874 struct tcpcb * 875 tcp_close(struct tcpcb *tp) 876 { 877 struct inpcb *inp = tp->t_inpcb; 878 struct socket *so; 879 880 INP_INFO_WLOCK_ASSERT(&V_tcbinfo); 881 INP_WLOCK_ASSERT(inp); 882 883 /* Notify any offload devices of listener close */ 884 if (tp->t_state == TCPS_LISTEN) 885 tcp_offload_listen_close(tp); 886 in_pcbdrop(inp); 887 TCPSTAT_INC(tcps_closed); 888 KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL")); 889 so = inp->inp_socket; 890 soisdisconnected(so); 891 if (inp->inp_flags & INP_SOCKREF) { 892 KASSERT(so->so_state & SS_PROTOREF, 893 ("tcp_close: !SS_PROTOREF")); 894 inp->inp_flags &= ~INP_SOCKREF; 895 INP_WUNLOCK(inp); 896 ACCEPT_LOCK(); 897 SOCK_LOCK(so); 898 so->so_state &= ~SS_PROTOREF; 899 sofree(so); 900 return (NULL); 901 } 902 return (tp); 903 } 904 905 void 906 tcp_drain(void) 907 { 908 VNET_ITERATOR_DECL(vnet_iter); 909 910 if (!do_tcpdrain) 911 return; 912 913 VNET_LIST_RLOCK_NOSLEEP(); 914 VNET_FOREACH(vnet_iter) { 915 CURVNET_SET(vnet_iter); 916 struct inpcb *inpb; 917 struct tcpcb *tcpb; 918 struct tseg_qent *te; 919 920 /* 921 * Walk the tcpbs, if existing, and flush the reassembly queue, 922 * if there is one... 923 * XXX: The "Net/3" implementation doesn't imply that the TCP 924 * reassembly queue should be flushed, but in a situation 925 * where we're really low on mbufs, this is potentially 926 * usefull. 927 */ 928 INP_INFO_RLOCK(&V_tcbinfo); 929 LIST_FOREACH(inpb, V_tcbinfo.ipi_listhead, inp_list) { 930 if (inpb->inp_flags & INP_TIMEWAIT) 931 continue; 932 INP_WLOCK(inpb); 933 if ((tcpb = intotcpcb(inpb)) != NULL) { 934 while ((te = LIST_FIRST(&tcpb->t_segq)) 935 != NULL) { 936 LIST_REMOVE(te, tqe_q); 937 m_freem(te->tqe_m); 938 uma_zfree(V_tcp_reass_zone, te); 939 tcpb->t_segqlen--; 940 V_tcp_reass_qsize--; 941 } 942 tcp_clean_sackreport(tcpb); 943 } 944 INP_WUNLOCK(inpb); 945 } 946 INP_INFO_RUNLOCK(&V_tcbinfo); 947 CURVNET_RESTORE(); 948 } 949 VNET_LIST_RUNLOCK_NOSLEEP(); 950 } 951 952 /* 953 * Notify a tcp user of an asynchronous error; 954 * store error as soft error, but wake up user 955 * (for now, won't do anything until can select for soft error). 956 * 957 * Do not wake up user since there currently is no mechanism for 958 * reporting soft errors (yet - a kqueue filter may be added). 959 */ 960 static struct inpcb * 961 tcp_notify(struct inpcb *inp, int error) 962 { 963 struct tcpcb *tp; 964 965 INP_INFO_WLOCK_ASSERT(&V_tcbinfo); 966 INP_WLOCK_ASSERT(inp); 967 968 if ((inp->inp_flags & INP_TIMEWAIT) || 969 (inp->inp_flags & INP_DROPPED)) 970 return (inp); 971 972 tp = intotcpcb(inp); 973 KASSERT(tp != NULL, ("tcp_notify: tp == NULL")); 974 975 /* 976 * Ignore some errors if we are hooked up. 977 * If connection hasn't completed, has retransmitted several times, 978 * and receives a second error, give up now. This is better 979 * than waiting a long time to establish a connection that 980 * can never complete. 981 */ 982 if (tp->t_state == TCPS_ESTABLISHED && 983 (error == EHOSTUNREACH || error == ENETUNREACH || 984 error == EHOSTDOWN)) { 985 return (inp); 986 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && 987 tp->t_softerror) { 988 tp = tcp_drop(tp, error); 989 if (tp != NULL) 990 return (inp); 991 else 992 return (NULL); 993 } else { 994 tp->t_softerror = error; 995 return (inp); 996 } 997 #if 0 998 wakeup( &so->so_timeo); 999 sorwakeup(so); 1000 sowwakeup(so); 1001 #endif 1002 } 1003 1004 static int 1005 tcp_pcblist(SYSCTL_HANDLER_ARGS) 1006 { 1007 int error, i, m, n, pcb_count; 1008 struct inpcb *inp, **inp_list; 1009 inp_gen_t gencnt; 1010 struct xinpgen xig; 1011 1012 /* 1013 * The process of preparing the TCB list is too time-consuming and 1014 * resource-intensive to repeat twice on every request. 1015 */ 1016 if (req->oldptr == NULL) { 1017 m = syncache_pcbcount(); 1018 n = V_tcbinfo.ipi_count; 1019 req->oldidx = 2 * (sizeof xig) 1020 + ((m + n) + n/8) * sizeof(struct xtcpcb); 1021 return (0); 1022 } 1023 1024 if (req->newptr != NULL) 1025 return (EPERM); 1026 1027 /* 1028 * OK, now we're committed to doing something. 1029 */ 1030 INP_INFO_RLOCK(&V_tcbinfo); 1031 gencnt = V_tcbinfo.ipi_gencnt; 1032 n = V_tcbinfo.ipi_count; 1033 INP_INFO_RUNLOCK(&V_tcbinfo); 1034 1035 m = syncache_pcbcount(); 1036 1037 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig) 1038 + (n + m) * sizeof(struct xtcpcb)); 1039 if (error != 0) 1040 return (error); 1041 1042 xig.xig_len = sizeof xig; 1043 xig.xig_count = n + m; 1044 xig.xig_gen = gencnt; 1045 xig.xig_sogen = so_gencnt; 1046 error = SYSCTL_OUT(req, &xig, sizeof xig); 1047 if (error) 1048 return (error); 1049 1050 error = syncache_pcblist(req, m, &pcb_count); 1051 if (error) 1052 return (error); 1053 1054 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 1055 if (inp_list == NULL) 1056 return (ENOMEM); 1057 1058 INP_INFO_RLOCK(&V_tcbinfo); 1059 for (inp = LIST_FIRST(V_tcbinfo.ipi_listhead), i = 0; 1060 inp != NULL && i < n; inp = LIST_NEXT(inp, inp_list)) { 1061 INP_WLOCK(inp); 1062 if (inp->inp_gencnt <= gencnt) { 1063 /* 1064 * XXX: This use of cr_cansee(), introduced with 1065 * TCP state changes, is not quite right, but for 1066 * now, better than nothing. 1067 */ 1068 if (inp->inp_flags & INP_TIMEWAIT) { 1069 if (intotw(inp) != NULL) 1070 error = cr_cansee(req->td->td_ucred, 1071 intotw(inp)->tw_cred); 1072 else 1073 error = EINVAL; /* Skip this inp. */ 1074 } else 1075 error = cr_canseeinpcb(req->td->td_ucred, inp); 1076 if (error == 0) { 1077 in_pcbref(inp); 1078 inp_list[i++] = inp; 1079 } 1080 } 1081 INP_WUNLOCK(inp); 1082 } 1083 INP_INFO_RUNLOCK(&V_tcbinfo); 1084 n = i; 1085 1086 error = 0; 1087 for (i = 0; i < n; i++) { 1088 inp = inp_list[i]; 1089 INP_RLOCK(inp); 1090 if (inp->inp_gencnt <= gencnt) { 1091 struct xtcpcb xt; 1092 void *inp_ppcb; 1093 1094 bzero(&xt, sizeof(xt)); 1095 xt.xt_len = sizeof xt; 1096 /* XXX should avoid extra copy */ 1097 bcopy(inp, &xt.xt_inp, sizeof *inp); 1098 inp_ppcb = inp->inp_ppcb; 1099 if (inp_ppcb == NULL) 1100 bzero((char *) &xt.xt_tp, sizeof xt.xt_tp); 1101 else if (inp->inp_flags & INP_TIMEWAIT) { 1102 bzero((char *) &xt.xt_tp, sizeof xt.xt_tp); 1103 xt.xt_tp.t_state = TCPS_TIME_WAIT; 1104 } else 1105 bcopy(inp_ppcb, &xt.xt_tp, sizeof xt.xt_tp); 1106 if (inp->inp_socket != NULL) 1107 sotoxsocket(inp->inp_socket, &xt.xt_socket); 1108 else { 1109 bzero(&xt.xt_socket, sizeof xt.xt_socket); 1110 xt.xt_socket.xso_protocol = IPPROTO_TCP; 1111 } 1112 xt.xt_inp.inp_gencnt = inp->inp_gencnt; 1113 INP_RUNLOCK(inp); 1114 error = SYSCTL_OUT(req, &xt, sizeof xt); 1115 } else 1116 INP_RUNLOCK(inp); 1117 } 1118 INP_INFO_WLOCK(&V_tcbinfo); 1119 for (i = 0; i < n; i++) { 1120 inp = inp_list[i]; 1121 INP_WLOCK(inp); 1122 if (!in_pcbrele(inp)) 1123 INP_WUNLOCK(inp); 1124 } 1125 INP_INFO_WUNLOCK(&V_tcbinfo); 1126 1127 if (!error) { 1128 /* 1129 * Give the user an updated idea of our state. 1130 * If the generation differs from what we told 1131 * her before, she knows that something happened 1132 * while we were processing this request, and it 1133 * might be necessary to retry. 1134 */ 1135 INP_INFO_RLOCK(&V_tcbinfo); 1136 xig.xig_gen = V_tcbinfo.ipi_gencnt; 1137 xig.xig_sogen = so_gencnt; 1138 xig.xig_count = V_tcbinfo.ipi_count + pcb_count; 1139 INP_INFO_RUNLOCK(&V_tcbinfo); 1140 error = SYSCTL_OUT(req, &xig, sizeof xig); 1141 } 1142 free(inp_list, M_TEMP); 1143 return (error); 1144 } 1145 1146 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0, 1147 tcp_pcblist, "S,xtcpcb", "List of active TCP connections"); 1148 1149 static int 1150 tcp_getcred(SYSCTL_HANDLER_ARGS) 1151 { 1152 struct xucred xuc; 1153 struct sockaddr_in addrs[2]; 1154 struct inpcb *inp; 1155 int error; 1156 1157 error = priv_check(req->td, PRIV_NETINET_GETCRED); 1158 if (error) 1159 return (error); 1160 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 1161 if (error) 1162 return (error); 1163 INP_INFO_RLOCK(&V_tcbinfo); 1164 inp = in_pcblookup_hash(&V_tcbinfo, addrs[1].sin_addr, 1165 addrs[1].sin_port, addrs[0].sin_addr, addrs[0].sin_port, 0, NULL); 1166 if (inp != NULL) { 1167 INP_RLOCK(inp); 1168 INP_INFO_RUNLOCK(&V_tcbinfo); 1169 if (inp->inp_socket == NULL) 1170 error = ENOENT; 1171 if (error == 0) 1172 error = cr_canseeinpcb(req->td->td_ucred, inp); 1173 if (error == 0) 1174 cru2x(inp->inp_cred, &xuc); 1175 INP_RUNLOCK(inp); 1176 } else { 1177 INP_INFO_RUNLOCK(&V_tcbinfo); 1178 error = ENOENT; 1179 } 1180 if (error == 0) 1181 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 1182 return (error); 1183 } 1184 1185 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, 1186 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 1187 tcp_getcred, "S,xucred", "Get the xucred of a TCP connection"); 1188 1189 #ifdef INET6 1190 static int 1191 tcp6_getcred(SYSCTL_HANDLER_ARGS) 1192 { 1193 struct xucred xuc; 1194 struct sockaddr_in6 addrs[2]; 1195 struct inpcb *inp; 1196 int error, mapped = 0; 1197 1198 error = priv_check(req->td, PRIV_NETINET_GETCRED); 1199 if (error) 1200 return (error); 1201 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 1202 if (error) 1203 return (error); 1204 if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 || 1205 (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) { 1206 return (error); 1207 } 1208 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) { 1209 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr)) 1210 mapped = 1; 1211 else 1212 return (EINVAL); 1213 } 1214 1215 INP_INFO_RLOCK(&V_tcbinfo); 1216 if (mapped == 1) 1217 inp = in_pcblookup_hash(&V_tcbinfo, 1218 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12], 1219 addrs[1].sin6_port, 1220 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12], 1221 addrs[0].sin6_port, 1222 0, NULL); 1223 else 1224 inp = in6_pcblookup_hash(&V_tcbinfo, 1225 &addrs[1].sin6_addr, addrs[1].sin6_port, 1226 &addrs[0].sin6_addr, addrs[0].sin6_port, 0, NULL); 1227 if (inp != NULL) { 1228 INP_RLOCK(inp); 1229 INP_INFO_RUNLOCK(&V_tcbinfo); 1230 if (inp->inp_socket == NULL) 1231 error = ENOENT; 1232 if (error == 0) 1233 error = cr_canseeinpcb(req->td->td_ucred, inp); 1234 if (error == 0) 1235 cru2x(inp->inp_cred, &xuc); 1236 INP_RUNLOCK(inp); 1237 } else { 1238 INP_INFO_RUNLOCK(&V_tcbinfo); 1239 error = ENOENT; 1240 } 1241 if (error == 0) 1242 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 1243 return (error); 1244 } 1245 1246 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, 1247 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 1248 tcp6_getcred, "S,xucred", "Get the xucred of a TCP6 connection"); 1249 #endif 1250 1251 1252 void 1253 tcp_ctlinput(int cmd, struct sockaddr *sa, void *vip) 1254 { 1255 struct ip *ip = vip; 1256 struct tcphdr *th; 1257 struct in_addr faddr; 1258 struct inpcb *inp; 1259 struct tcpcb *tp; 1260 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify; 1261 struct icmp *icp; 1262 struct in_conninfo inc; 1263 tcp_seq icmp_tcp_seq; 1264 int mtu; 1265 1266 faddr = ((struct sockaddr_in *)sa)->sin_addr; 1267 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 1268 return; 1269 1270 if (cmd == PRC_MSGSIZE) 1271 notify = tcp_mtudisc; 1272 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB || 1273 cmd == PRC_UNREACH_PORT || cmd == PRC_TIMXCEED_INTRANS) && ip) 1274 notify = tcp_drop_syn_sent; 1275 /* 1276 * Redirects don't need to be handled up here. 1277 */ 1278 else if (PRC_IS_REDIRECT(cmd)) 1279 return; 1280 /* 1281 * Source quench is depreciated. 1282 */ 1283 else if (cmd == PRC_QUENCH) 1284 return; 1285 /* 1286 * Hostdead is ugly because it goes linearly through all PCBs. 1287 * XXX: We never get this from ICMP, otherwise it makes an 1288 * excellent DoS attack on machines with many connections. 1289 */ 1290 else if (cmd == PRC_HOSTDEAD) 1291 ip = NULL; 1292 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 1293 return; 1294 if (ip != NULL) { 1295 icp = (struct icmp *)((caddr_t)ip 1296 - offsetof(struct icmp, icmp_ip)); 1297 th = (struct tcphdr *)((caddr_t)ip 1298 + (ip->ip_hl << 2)); 1299 INP_INFO_WLOCK(&V_tcbinfo); 1300 inp = in_pcblookup_hash(&V_tcbinfo, faddr, th->th_dport, 1301 ip->ip_src, th->th_sport, 0, NULL); 1302 if (inp != NULL) { 1303 INP_WLOCK(inp); 1304 if (!(inp->inp_flags & INP_TIMEWAIT) && 1305 !(inp->inp_flags & INP_DROPPED) && 1306 !(inp->inp_socket == NULL)) { 1307 icmp_tcp_seq = htonl(th->th_seq); 1308 tp = intotcpcb(inp); 1309 if (SEQ_GEQ(icmp_tcp_seq, tp->snd_una) && 1310 SEQ_LT(icmp_tcp_seq, tp->snd_max)) { 1311 if (cmd == PRC_MSGSIZE) { 1312 /* 1313 * MTU discovery: 1314 * If we got a needfrag set the MTU 1315 * in the route to the suggested new 1316 * value (if given) and then notify. 1317 */ 1318 bzero(&inc, sizeof(inc)); 1319 inc.inc_faddr = faddr; 1320 inc.inc_fibnum = 1321 inp->inp_inc.inc_fibnum; 1322 1323 mtu = ntohs(icp->icmp_nextmtu); 1324 /* 1325 * If no alternative MTU was 1326 * proposed, try the next smaller 1327 * one. ip->ip_len has already 1328 * been swapped in icmp_input(). 1329 */ 1330 if (!mtu) 1331 mtu = ip_next_mtu(ip->ip_len, 1332 1); 1333 if (mtu < max(296, V_tcp_minmss 1334 + sizeof(struct tcpiphdr))) 1335 mtu = 0; 1336 if (!mtu) 1337 mtu = V_tcp_mssdflt 1338 + sizeof(struct tcpiphdr); 1339 /* 1340 * Only cache the the MTU if it 1341 * is smaller than the interface 1342 * or route MTU. tcp_mtudisc() 1343 * will do right thing by itself. 1344 */ 1345 if (mtu <= tcp_maxmtu(&inc, NULL)) 1346 tcp_hc_updatemtu(&inc, mtu); 1347 } 1348 1349 inp = (*notify)(inp, inetctlerrmap[cmd]); 1350 } 1351 } 1352 if (inp != NULL) 1353 INP_WUNLOCK(inp); 1354 } else { 1355 bzero(&inc, sizeof(inc)); 1356 inc.inc_fport = th->th_dport; 1357 inc.inc_lport = th->th_sport; 1358 inc.inc_faddr = faddr; 1359 inc.inc_laddr = ip->ip_src; 1360 syncache_unreach(&inc, th); 1361 } 1362 INP_INFO_WUNLOCK(&V_tcbinfo); 1363 } else 1364 in_pcbnotifyall(&V_tcbinfo, faddr, inetctlerrmap[cmd], notify); 1365 } 1366 1367 #ifdef INET6 1368 void 1369 tcp6_ctlinput(int cmd, struct sockaddr *sa, void *d) 1370 { 1371 struct tcphdr th; 1372 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify; 1373 struct ip6_hdr *ip6; 1374 struct mbuf *m; 1375 struct ip6ctlparam *ip6cp = NULL; 1376 const struct sockaddr_in6 *sa6_src = NULL; 1377 int off; 1378 struct tcp_portonly { 1379 u_int16_t th_sport; 1380 u_int16_t th_dport; 1381 } *thp; 1382 1383 if (sa->sa_family != AF_INET6 || 1384 sa->sa_len != sizeof(struct sockaddr_in6)) 1385 return; 1386 1387 if (cmd == PRC_MSGSIZE) 1388 notify = tcp_mtudisc; 1389 else if (!PRC_IS_REDIRECT(cmd) && 1390 ((unsigned)cmd >= PRC_NCMDS || inet6ctlerrmap[cmd] == 0)) 1391 return; 1392 /* Source quench is depreciated. */ 1393 else if (cmd == PRC_QUENCH) 1394 return; 1395 1396 /* if the parameter is from icmp6, decode it. */ 1397 if (d != NULL) { 1398 ip6cp = (struct ip6ctlparam *)d; 1399 m = ip6cp->ip6c_m; 1400 ip6 = ip6cp->ip6c_ip6; 1401 off = ip6cp->ip6c_off; 1402 sa6_src = ip6cp->ip6c_src; 1403 } else { 1404 m = NULL; 1405 ip6 = NULL; 1406 off = 0; /* fool gcc */ 1407 sa6_src = &sa6_any; 1408 } 1409 1410 if (ip6 != NULL) { 1411 struct in_conninfo inc; 1412 /* 1413 * XXX: We assume that when IPV6 is non NULL, 1414 * M and OFF are valid. 1415 */ 1416 1417 /* check if we can safely examine src and dst ports */ 1418 if (m->m_pkthdr.len < off + sizeof(*thp)) 1419 return; 1420 1421 bzero(&th, sizeof(th)); 1422 m_copydata(m, off, sizeof(*thp), (caddr_t)&th); 1423 1424 in6_pcbnotify(&V_tcbinfo, sa, th.th_dport, 1425 (struct sockaddr *)ip6cp->ip6c_src, 1426 th.th_sport, cmd, NULL, notify); 1427 1428 bzero(&inc, sizeof(inc)); 1429 inc.inc_fport = th.th_dport; 1430 inc.inc_lport = th.th_sport; 1431 inc.inc6_faddr = ((struct sockaddr_in6 *)sa)->sin6_addr; 1432 inc.inc6_laddr = ip6cp->ip6c_src->sin6_addr; 1433 inc.inc_flags |= INC_ISIPV6; 1434 INP_INFO_WLOCK(&V_tcbinfo); 1435 syncache_unreach(&inc, &th); 1436 INP_INFO_WUNLOCK(&V_tcbinfo); 1437 } else 1438 in6_pcbnotify(&V_tcbinfo, sa, 0, (const struct sockaddr *)sa6_src, 1439 0, cmd, NULL, notify); 1440 } 1441 #endif /* INET6 */ 1442 1443 1444 /* 1445 * Following is where TCP initial sequence number generation occurs. 1446 * 1447 * There are two places where we must use initial sequence numbers: 1448 * 1. In SYN-ACK packets. 1449 * 2. In SYN packets. 1450 * 1451 * All ISNs for SYN-ACK packets are generated by the syncache. See 1452 * tcp_syncache.c for details. 1453 * 1454 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling 1455 * depends on this property. In addition, these ISNs should be 1456 * unguessable so as to prevent connection hijacking. To satisfy 1457 * the requirements of this situation, the algorithm outlined in 1458 * RFC 1948 is used, with only small modifications. 1459 * 1460 * Implementation details: 1461 * 1462 * Time is based off the system timer, and is corrected so that it 1463 * increases by one megabyte per second. This allows for proper 1464 * recycling on high speed LANs while still leaving over an hour 1465 * before rollover. 1466 * 1467 * As reading the *exact* system time is too expensive to be done 1468 * whenever setting up a TCP connection, we increment the time 1469 * offset in two ways. First, a small random positive increment 1470 * is added to isn_offset for each connection that is set up. 1471 * Second, the function tcp_isn_tick fires once per clock tick 1472 * and increments isn_offset as necessary so that sequence numbers 1473 * are incremented at approximately ISN_BYTES_PER_SECOND. The 1474 * random positive increments serve only to ensure that the same 1475 * exact sequence number is never sent out twice (as could otherwise 1476 * happen when a port is recycled in less than the system tick 1477 * interval.) 1478 * 1479 * net.inet.tcp.isn_reseed_interval controls the number of seconds 1480 * between seeding of isn_secret. This is normally set to zero, 1481 * as reseeding should not be necessary. 1482 * 1483 * Locking of the global variables isn_secret, isn_last_reseed, isn_offset, 1484 * isn_offset_old, and isn_ctx is performed using the TCP pcbinfo lock. In 1485 * general, this means holding an exclusive (write) lock. 1486 */ 1487 1488 #define ISN_BYTES_PER_SECOND 1048576 1489 #define ISN_STATIC_INCREMENT 4096 1490 #define ISN_RANDOM_INCREMENT (4096 - 1) 1491 1492 static VNET_DEFINE(u_char, isn_secret[32]); 1493 static VNET_DEFINE(int, isn_last_reseed); 1494 static VNET_DEFINE(u_int32_t, isn_offset); 1495 static VNET_DEFINE(u_int32_t, isn_offset_old); 1496 1497 #define V_isn_secret VNET(isn_secret) 1498 #define V_isn_last_reseed VNET(isn_last_reseed) 1499 #define V_isn_offset VNET(isn_offset) 1500 #define V_isn_offset_old VNET(isn_offset_old) 1501 1502 tcp_seq 1503 tcp_new_isn(struct tcpcb *tp) 1504 { 1505 MD5_CTX isn_ctx; 1506 u_int32_t md5_buffer[4]; 1507 tcp_seq new_isn; 1508 1509 INP_WLOCK_ASSERT(tp->t_inpcb); 1510 1511 ISN_LOCK(); 1512 /* Seed if this is the first use, reseed if requested. */ 1513 if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) && 1514 (((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz) 1515 < (u_int)ticks))) { 1516 read_random(&V_isn_secret, sizeof(V_isn_secret)); 1517 V_isn_last_reseed = ticks; 1518 } 1519 1520 /* Compute the md5 hash and return the ISN. */ 1521 MD5Init(&isn_ctx); 1522 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_fport, sizeof(u_short)); 1523 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_lport, sizeof(u_short)); 1524 #ifdef INET6 1525 if ((tp->t_inpcb->inp_vflag & INP_IPV6) != 0) { 1526 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_faddr, 1527 sizeof(struct in6_addr)); 1528 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_laddr, 1529 sizeof(struct in6_addr)); 1530 } else 1531 #endif 1532 { 1533 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_faddr, 1534 sizeof(struct in_addr)); 1535 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_laddr, 1536 sizeof(struct in_addr)); 1537 } 1538 MD5Update(&isn_ctx, (u_char *) &V_isn_secret, sizeof(V_isn_secret)); 1539 MD5Final((u_char *) &md5_buffer, &isn_ctx); 1540 new_isn = (tcp_seq) md5_buffer[0]; 1541 V_isn_offset += ISN_STATIC_INCREMENT + 1542 (arc4random() & ISN_RANDOM_INCREMENT); 1543 new_isn += V_isn_offset; 1544 ISN_UNLOCK(); 1545 return (new_isn); 1546 } 1547 1548 /* 1549 * Increment the offset to the next ISN_BYTES_PER_SECOND / 100 boundary 1550 * to keep time flowing at a relatively constant rate. If the random 1551 * increments have already pushed us past the projected offset, do nothing. 1552 */ 1553 static void 1554 tcp_isn_tick(void *xtp) 1555 { 1556 VNET_ITERATOR_DECL(vnet_iter); 1557 u_int32_t projected_offset; 1558 1559 VNET_LIST_RLOCK_NOSLEEP(); 1560 ISN_LOCK(); 1561 VNET_FOREACH(vnet_iter) { 1562 CURVNET_SET(vnet_iter); /* XXX appease INVARIANTS */ 1563 projected_offset = 1564 V_isn_offset_old + ISN_BYTES_PER_SECOND / 100; 1565 1566 if (SEQ_GT(projected_offset, V_isn_offset)) 1567 V_isn_offset = projected_offset; 1568 1569 V_isn_offset_old = V_isn_offset; 1570 CURVNET_RESTORE(); 1571 } 1572 ISN_UNLOCK(); 1573 VNET_LIST_RUNLOCK_NOSLEEP(); 1574 callout_reset(&isn_callout, hz/100, tcp_isn_tick, NULL); 1575 } 1576 1577 /* 1578 * When a specific ICMP unreachable message is received and the 1579 * connection state is SYN-SENT, drop the connection. This behavior 1580 * is controlled by the icmp_may_rst sysctl. 1581 */ 1582 struct inpcb * 1583 tcp_drop_syn_sent(struct inpcb *inp, int errno) 1584 { 1585 struct tcpcb *tp; 1586 1587 INP_INFO_WLOCK_ASSERT(&V_tcbinfo); 1588 INP_WLOCK_ASSERT(inp); 1589 1590 if ((inp->inp_flags & INP_TIMEWAIT) || 1591 (inp->inp_flags & INP_DROPPED)) 1592 return (inp); 1593 1594 tp = intotcpcb(inp); 1595 if (tp->t_state != TCPS_SYN_SENT) 1596 return (inp); 1597 1598 tp = tcp_drop(tp, errno); 1599 if (tp != NULL) 1600 return (inp); 1601 else 1602 return (NULL); 1603 } 1604 1605 /* 1606 * When `need fragmentation' ICMP is received, update our idea of the MSS 1607 * based on the new value in the route. Also nudge TCP to send something, 1608 * since we know the packet we just sent was dropped. 1609 * This duplicates some code in the tcp_mss() function in tcp_input.c. 1610 */ 1611 struct inpcb * 1612 tcp_mtudisc(struct inpcb *inp, int errno) 1613 { 1614 struct tcpcb *tp; 1615 struct socket *so; 1616 1617 INP_WLOCK_ASSERT(inp); 1618 if ((inp->inp_flags & INP_TIMEWAIT) || 1619 (inp->inp_flags & INP_DROPPED)) 1620 return (inp); 1621 1622 tp = intotcpcb(inp); 1623 KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL")); 1624 1625 tcp_mss_update(tp, -1, NULL, NULL); 1626 1627 so = inp->inp_socket; 1628 SOCKBUF_LOCK(&so->so_snd); 1629 /* If the mss is larger than the socket buffer, decrease the mss. */ 1630 if (so->so_snd.sb_hiwat < tp->t_maxseg) 1631 tp->t_maxseg = so->so_snd.sb_hiwat; 1632 SOCKBUF_UNLOCK(&so->so_snd); 1633 1634 TCPSTAT_INC(tcps_mturesent); 1635 tp->t_rtttime = 0; 1636 tp->snd_nxt = tp->snd_una; 1637 tcp_free_sackholes(tp); 1638 tp->snd_recover = tp->snd_max; 1639 if (tp->t_flags & TF_SACK_PERMIT) 1640 EXIT_FASTRECOVERY(tp); 1641 tcp_output_send(tp); 1642 return (inp); 1643 } 1644 1645 /* 1646 * Look-up the routing entry to the peer of this inpcb. If no route 1647 * is found and it cannot be allocated, then return 0. This routine 1648 * is called by TCP routines that access the rmx structure and by 1649 * tcp_mss_update to get the peer/interface MTU. 1650 */ 1651 u_long 1652 tcp_maxmtu(struct in_conninfo *inc, int *flags) 1653 { 1654 struct route sro; 1655 struct sockaddr_in *dst; 1656 struct ifnet *ifp; 1657 u_long maxmtu = 0; 1658 1659 KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer")); 1660 1661 bzero(&sro, sizeof(sro)); 1662 if (inc->inc_faddr.s_addr != INADDR_ANY) { 1663 dst = (struct sockaddr_in *)&sro.ro_dst; 1664 dst->sin_family = AF_INET; 1665 dst->sin_len = sizeof(*dst); 1666 dst->sin_addr = inc->inc_faddr; 1667 in_rtalloc_ign(&sro, 0, inc->inc_fibnum); 1668 } 1669 if (sro.ro_rt != NULL) { 1670 ifp = sro.ro_rt->rt_ifp; 1671 if (sro.ro_rt->rt_rmx.rmx_mtu == 0) 1672 maxmtu = ifp->if_mtu; 1673 else 1674 maxmtu = min(sro.ro_rt->rt_rmx.rmx_mtu, ifp->if_mtu); 1675 1676 /* Report additional interface capabilities. */ 1677 if (flags != NULL) { 1678 if (ifp->if_capenable & IFCAP_TSO4 && 1679 ifp->if_hwassist & CSUM_TSO) 1680 *flags |= CSUM_TSO; 1681 } 1682 RTFREE(sro.ro_rt); 1683 } 1684 return (maxmtu); 1685 } 1686 1687 #ifdef INET6 1688 u_long 1689 tcp_maxmtu6(struct in_conninfo *inc, int *flags) 1690 { 1691 struct route_in6 sro6; 1692 struct ifnet *ifp; 1693 u_long maxmtu = 0; 1694 1695 KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer")); 1696 1697 bzero(&sro6, sizeof(sro6)); 1698 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) { 1699 sro6.ro_dst.sin6_family = AF_INET6; 1700 sro6.ro_dst.sin6_len = sizeof(struct sockaddr_in6); 1701 sro6.ro_dst.sin6_addr = inc->inc6_faddr; 1702 rtalloc_ign((struct route *)&sro6, 0); 1703 } 1704 if (sro6.ro_rt != NULL) { 1705 ifp = sro6.ro_rt->rt_ifp; 1706 if (sro6.ro_rt->rt_rmx.rmx_mtu == 0) 1707 maxmtu = IN6_LINKMTU(sro6.ro_rt->rt_ifp); 1708 else 1709 maxmtu = min(sro6.ro_rt->rt_rmx.rmx_mtu, 1710 IN6_LINKMTU(sro6.ro_rt->rt_ifp)); 1711 1712 /* Report additional interface capabilities. */ 1713 if (flags != NULL) { 1714 if (ifp->if_capenable & IFCAP_TSO6 && 1715 ifp->if_hwassist & CSUM_TSO) 1716 *flags |= CSUM_TSO; 1717 } 1718 RTFREE(sro6.ro_rt); 1719 } 1720 1721 return (maxmtu); 1722 } 1723 #endif /* INET6 */ 1724 1725 #ifdef IPSEC 1726 /* compute ESP/AH header size for TCP, including outer IP header. */ 1727 size_t 1728 ipsec_hdrsiz_tcp(struct tcpcb *tp) 1729 { 1730 struct inpcb *inp; 1731 struct mbuf *m; 1732 size_t hdrsiz; 1733 struct ip *ip; 1734 #ifdef INET6 1735 struct ip6_hdr *ip6; 1736 #endif 1737 struct tcphdr *th; 1738 1739 if ((tp == NULL) || ((inp = tp->t_inpcb) == NULL)) 1740 return (0); 1741 MGETHDR(m, M_DONTWAIT, MT_DATA); 1742 if (!m) 1743 return (0); 1744 1745 #ifdef INET6 1746 if ((inp->inp_vflag & INP_IPV6) != 0) { 1747 ip6 = mtod(m, struct ip6_hdr *); 1748 th = (struct tcphdr *)(ip6 + 1); 1749 m->m_pkthdr.len = m->m_len = 1750 sizeof(struct ip6_hdr) + sizeof(struct tcphdr); 1751 tcpip_fillheaders(inp, ip6, th); 1752 hdrsiz = ipsec_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp); 1753 } else 1754 #endif /* INET6 */ 1755 { 1756 ip = mtod(m, struct ip *); 1757 th = (struct tcphdr *)(ip + 1); 1758 m->m_pkthdr.len = m->m_len = sizeof(struct tcpiphdr); 1759 tcpip_fillheaders(inp, ip, th); 1760 hdrsiz = ipsec_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp); 1761 } 1762 1763 m_free(m); 1764 return (hdrsiz); 1765 } 1766 #endif /* IPSEC */ 1767 1768 /* 1769 * TCP BANDWIDTH DELAY PRODUCT WINDOW LIMITING 1770 * 1771 * This code attempts to calculate the bandwidth-delay product as a 1772 * means of determining the optimal window size to maximize bandwidth, 1773 * minimize RTT, and avoid the over-allocation of buffers on interfaces and 1774 * routers. This code also does a fairly good job keeping RTTs in check 1775 * across slow links like modems. We implement an algorithm which is very 1776 * similar (but not meant to be) TCP/Vegas. The code operates on the 1777 * transmitter side of a TCP connection and so only effects the transmit 1778 * side of the connection. 1779 * 1780 * BACKGROUND: TCP makes no provision for the management of buffer space 1781 * at the end points or at the intermediate routers and switches. A TCP 1782 * stream, whether using NewReno or not, will eventually buffer as 1783 * many packets as it is able and the only reason this typically works is 1784 * due to the fairly small default buffers made available for a connection 1785 * (typicaly 16K or 32K). As machines use larger windows and/or window 1786 * scaling it is now fairly easy for even a single TCP connection to blow-out 1787 * all available buffer space not only on the local interface, but on 1788 * intermediate routers and switches as well. NewReno makes a misguided 1789 * attempt to 'solve' this problem by waiting for an actual failure to occur, 1790 * then backing off, then steadily increasing the window again until another 1791 * failure occurs, ad-infinitum. This results in terrible oscillation that 1792 * is only made worse as network loads increase and the idea of intentionally 1793 * blowing out network buffers is, frankly, a terrible way to manage network 1794 * resources. 1795 * 1796 * It is far better to limit the transmit window prior to the failure 1797 * condition being achieved. There are two general ways to do this: First 1798 * you can 'scan' through different transmit window sizes and locate the 1799 * point where the RTT stops increasing, indicating that you have filled the 1800 * pipe, then scan backwards until you note that RTT stops decreasing, then 1801 * repeat ad-infinitum. This method works in principle but has severe 1802 * implementation issues due to RTT variances, timer granularity, and 1803 * instability in the algorithm which can lead to many false positives and 1804 * create oscillations as well as interact badly with other TCP streams 1805 * implementing the same algorithm. 1806 * 1807 * The second method is to limit the window to the bandwidth delay product 1808 * of the link. This is the method we implement. RTT variances and our 1809 * own manipulation of the congestion window, bwnd, can potentially 1810 * destabilize the algorithm. For this reason we have to stabilize the 1811 * elements used to calculate the window. We do this by using the minimum 1812 * observed RTT, the long term average of the observed bandwidth, and 1813 * by adding two segments worth of slop. It isn't perfect but it is able 1814 * to react to changing conditions and gives us a very stable basis on 1815 * which to extend the algorithm. 1816 */ 1817 void 1818 tcp_xmit_bandwidth_limit(struct tcpcb *tp, tcp_seq ack_seq) 1819 { 1820 u_long bw; 1821 u_long bwnd; 1822 int save_ticks; 1823 1824 INP_WLOCK_ASSERT(tp->t_inpcb); 1825 1826 /* 1827 * If inflight_enable is disabled in the middle of a tcp connection, 1828 * make sure snd_bwnd is effectively disabled. 1829 */ 1830 if (V_tcp_inflight_enable == 0 || 1831 tp->t_rttlow < V_tcp_inflight_rttthresh) { 1832 tp->snd_bwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 1833 tp->snd_bandwidth = 0; 1834 return; 1835 } 1836 1837 /* 1838 * Figure out the bandwidth. Due to the tick granularity this 1839 * is a very rough number and it MUST be averaged over a fairly 1840 * long period of time. XXX we need to take into account a link 1841 * that is not using all available bandwidth, but for now our 1842 * slop will ramp us up if this case occurs and the bandwidth later 1843 * increases. 1844 * 1845 * Note: if ticks rollover 'bw' may wind up negative. We must 1846 * effectively reset t_bw_rtttime for this case. 1847 */ 1848 save_ticks = ticks; 1849 if ((u_int)(save_ticks - tp->t_bw_rtttime) < 1) 1850 return; 1851 1852 bw = (int64_t)(ack_seq - tp->t_bw_rtseq) * hz / 1853 (save_ticks - tp->t_bw_rtttime); 1854 tp->t_bw_rtttime = save_ticks; 1855 tp->t_bw_rtseq = ack_seq; 1856 if (tp->t_bw_rtttime == 0 || (int)bw < 0) 1857 return; 1858 bw = ((int64_t)tp->snd_bandwidth * 15 + bw) >> 4; 1859 1860 tp->snd_bandwidth = bw; 1861 1862 /* 1863 * Calculate the semi-static bandwidth delay product, plus two maximal 1864 * segments. The additional slop puts us squarely in the sweet 1865 * spot and also handles the bandwidth run-up case and stabilization. 1866 * Without the slop we could be locking ourselves into a lower 1867 * bandwidth. 1868 * 1869 * Situations Handled: 1870 * (1) Prevents over-queueing of packets on LANs, especially on 1871 * high speed LANs, allowing larger TCP buffers to be 1872 * specified, and also does a good job preventing 1873 * over-queueing of packets over choke points like modems 1874 * (at least for the transmit side). 1875 * 1876 * (2) Is able to handle changing network loads (bandwidth 1877 * drops so bwnd drops, bandwidth increases so bwnd 1878 * increases). 1879 * 1880 * (3) Theoretically should stabilize in the face of multiple 1881 * connections implementing the same algorithm (this may need 1882 * a little work). 1883 * 1884 * (4) Stability value (defaults to 20 = 2 maximal packets) can 1885 * be adjusted with a sysctl but typically only needs to be 1886 * on very slow connections. A value no smaller then 5 1887 * should be used, but only reduce this default if you have 1888 * no other choice. 1889 */ 1890 #define USERTT ((tp->t_srtt + tp->t_rttbest) / 2) 1891 bwnd = (int64_t)bw * USERTT / (hz << TCP_RTT_SHIFT) + V_tcp_inflight_stab * tp->t_maxseg / 10; 1892 #undef USERTT 1893 1894 if (tcp_inflight_debug > 0) { 1895 static int ltime; 1896 if ((u_int)(ticks - ltime) >= hz / tcp_inflight_debug) { 1897 ltime = ticks; 1898 printf("%p bw %ld rttbest %d srtt %d bwnd %ld\n", 1899 tp, 1900 bw, 1901 tp->t_rttbest, 1902 tp->t_srtt, 1903 bwnd 1904 ); 1905 } 1906 } 1907 if ((long)bwnd < V_tcp_inflight_min) 1908 bwnd = V_tcp_inflight_min; 1909 if (bwnd > V_tcp_inflight_max) 1910 bwnd = V_tcp_inflight_max; 1911 if ((long)bwnd < tp->t_maxseg * 2) 1912 bwnd = tp->t_maxseg * 2; 1913 tp->snd_bwnd = bwnd; 1914 } 1915 1916 #ifdef TCP_SIGNATURE 1917 /* 1918 * Callback function invoked by m_apply() to digest TCP segment data 1919 * contained within an mbuf chain. 1920 */ 1921 static int 1922 tcp_signature_apply(void *fstate, void *data, u_int len) 1923 { 1924 1925 MD5Update(fstate, (u_char *)data, len); 1926 return (0); 1927 } 1928 1929 /* 1930 * Compute TCP-MD5 hash of a TCP segment. (RFC2385) 1931 * 1932 * Parameters: 1933 * m pointer to head of mbuf chain 1934 * _unused 1935 * len length of TCP segment data, excluding options 1936 * optlen length of TCP segment options 1937 * buf pointer to storage for computed MD5 digest 1938 * direction direction of flow (IPSEC_DIR_INBOUND or OUTBOUND) 1939 * 1940 * We do this over ip, tcphdr, segment data, and the key in the SADB. 1941 * When called from tcp_input(), we can be sure that th_sum has been 1942 * zeroed out and verified already. 1943 * 1944 * Return 0 if successful, otherwise return -1. 1945 * 1946 * XXX The key is retrieved from the system's PF_KEY SADB, by keying a 1947 * search with the destination IP address, and a 'magic SPI' to be 1948 * determined by the application. This is hardcoded elsewhere to 1179 1949 * right now. Another branch of this code exists which uses the SPD to 1950 * specify per-application flows but it is unstable. 1951 */ 1952 int 1953 tcp_signature_compute(struct mbuf *m, int _unused, int len, int optlen, 1954 u_char *buf, u_int direction) 1955 { 1956 union sockaddr_union dst; 1957 struct ippseudo ippseudo; 1958 MD5_CTX ctx; 1959 int doff; 1960 struct ip *ip; 1961 struct ipovly *ipovly; 1962 struct secasvar *sav; 1963 struct tcphdr *th; 1964 #ifdef INET6 1965 struct ip6_hdr *ip6; 1966 struct in6_addr in6; 1967 char ip6buf[INET6_ADDRSTRLEN]; 1968 uint32_t plen; 1969 uint16_t nhdr; 1970 #endif 1971 u_short savecsum; 1972 1973 KASSERT(m != NULL, ("NULL mbuf chain")); 1974 KASSERT(buf != NULL, ("NULL signature pointer")); 1975 1976 /* Extract the destination from the IP header in the mbuf. */ 1977 bzero(&dst, sizeof(union sockaddr_union)); 1978 ip = mtod(m, struct ip *); 1979 #ifdef INET6 1980 ip6 = NULL; /* Make the compiler happy. */ 1981 #endif 1982 switch (ip->ip_v) { 1983 case IPVERSION: 1984 dst.sa.sa_len = sizeof(struct sockaddr_in); 1985 dst.sa.sa_family = AF_INET; 1986 dst.sin.sin_addr = (direction == IPSEC_DIR_INBOUND) ? 1987 ip->ip_src : ip->ip_dst; 1988 break; 1989 #ifdef INET6 1990 case (IPV6_VERSION >> 4): 1991 ip6 = mtod(m, struct ip6_hdr *); 1992 dst.sa.sa_len = sizeof(struct sockaddr_in6); 1993 dst.sa.sa_family = AF_INET6; 1994 dst.sin6.sin6_addr = (direction == IPSEC_DIR_INBOUND) ? 1995 ip6->ip6_src : ip6->ip6_dst; 1996 break; 1997 #endif 1998 default: 1999 return (EINVAL); 2000 /* NOTREACHED */ 2001 break; 2002 } 2003 2004 /* Look up an SADB entry which matches the address of the peer. */ 2005 sav = KEY_ALLOCSA(&dst, IPPROTO_TCP, htonl(TCP_SIG_SPI)); 2006 if (sav == NULL) { 2007 ipseclog((LOG_ERR, "%s: SADB lookup failed for %s\n", __func__, 2008 (ip->ip_v == IPVERSION) ? inet_ntoa(dst.sin.sin_addr) : 2009 #ifdef INET6 2010 (ip->ip_v == (IPV6_VERSION >> 4)) ? 2011 ip6_sprintf(ip6buf, &dst.sin6.sin6_addr) : 2012 #endif 2013 "(unsupported)")); 2014 return (EINVAL); 2015 } 2016 2017 MD5Init(&ctx); 2018 /* 2019 * Step 1: Update MD5 hash with IP(v6) pseudo-header. 2020 * 2021 * XXX The ippseudo header MUST be digested in network byte order, 2022 * or else we'll fail the regression test. Assume all fields we've 2023 * been doing arithmetic on have been in host byte order. 2024 * XXX One cannot depend on ipovly->ih_len here. When called from 2025 * tcp_output(), the underlying ip_len member has not yet been set. 2026 */ 2027 switch (ip->ip_v) { 2028 case IPVERSION: 2029 ipovly = (struct ipovly *)ip; 2030 ippseudo.ippseudo_src = ipovly->ih_src; 2031 ippseudo.ippseudo_dst = ipovly->ih_dst; 2032 ippseudo.ippseudo_pad = 0; 2033 ippseudo.ippseudo_p = IPPROTO_TCP; 2034 ippseudo.ippseudo_len = htons(len + sizeof(struct tcphdr) + 2035 optlen); 2036 MD5Update(&ctx, (char *)&ippseudo, sizeof(struct ippseudo)); 2037 2038 th = (struct tcphdr *)((u_char *)ip + sizeof(struct ip)); 2039 doff = sizeof(struct ip) + sizeof(struct tcphdr) + optlen; 2040 break; 2041 #ifdef INET6 2042 /* 2043 * RFC 2385, 2.0 Proposal 2044 * For IPv6, the pseudo-header is as described in RFC 2460, namely the 2045 * 128-bit source IPv6 address, 128-bit destination IPv6 address, zero- 2046 * extended next header value (to form 32 bits), and 32-bit segment 2047 * length. 2048 * Note: Upper-Layer Packet Length comes before Next Header. 2049 */ 2050 case (IPV6_VERSION >> 4): 2051 in6 = ip6->ip6_src; 2052 in6_clearscope(&in6); 2053 MD5Update(&ctx, (char *)&in6, sizeof(struct in6_addr)); 2054 in6 = ip6->ip6_dst; 2055 in6_clearscope(&in6); 2056 MD5Update(&ctx, (char *)&in6, sizeof(struct in6_addr)); 2057 plen = htonl(len + sizeof(struct tcphdr) + optlen); 2058 MD5Update(&ctx, (char *)&plen, sizeof(uint32_t)); 2059 nhdr = 0; 2060 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t)); 2061 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t)); 2062 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t)); 2063 nhdr = IPPROTO_TCP; 2064 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t)); 2065 2066 th = (struct tcphdr *)((u_char *)ip6 + sizeof(struct ip6_hdr)); 2067 doff = sizeof(struct ip6_hdr) + sizeof(struct tcphdr) + optlen; 2068 break; 2069 #endif 2070 default: 2071 return (EINVAL); 2072 /* NOTREACHED */ 2073 break; 2074 } 2075 2076 2077 /* 2078 * Step 2: Update MD5 hash with TCP header, excluding options. 2079 * The TCP checksum must be set to zero. 2080 */ 2081 savecsum = th->th_sum; 2082 th->th_sum = 0; 2083 MD5Update(&ctx, (char *)th, sizeof(struct tcphdr)); 2084 th->th_sum = savecsum; 2085 2086 /* 2087 * Step 3: Update MD5 hash with TCP segment data. 2088 * Use m_apply() to avoid an early m_pullup(). 2089 */ 2090 if (len > 0) 2091 m_apply(m, doff, len, tcp_signature_apply, &ctx); 2092 2093 /* 2094 * Step 4: Update MD5 hash with shared secret. 2095 */ 2096 MD5Update(&ctx, sav->key_auth->key_data, _KEYLEN(sav->key_auth)); 2097 MD5Final(buf, &ctx); 2098 2099 key_sa_recordxfer(sav, m); 2100 KEY_FREESAV(&sav); 2101 return (0); 2102 } 2103 #endif /* TCP_SIGNATURE */ 2104 2105 static int 2106 sysctl_drop(SYSCTL_HANDLER_ARGS) 2107 { 2108 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 2109 struct sockaddr_storage addrs[2]; 2110 struct inpcb *inp; 2111 struct tcpcb *tp; 2112 struct tcptw *tw; 2113 struct sockaddr_in *fin, *lin; 2114 #ifdef INET6 2115 struct sockaddr_in6 *fin6, *lin6; 2116 #endif 2117 int error; 2118 2119 inp = NULL; 2120 fin = lin = NULL; 2121 #ifdef INET6 2122 fin6 = lin6 = NULL; 2123 #endif 2124 error = 0; 2125 2126 if (req->oldptr != NULL || req->oldlen != 0) 2127 return (EINVAL); 2128 if (req->newptr == NULL) 2129 return (EPERM); 2130 if (req->newlen < sizeof(addrs)) 2131 return (ENOMEM); 2132 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 2133 if (error) 2134 return (error); 2135 2136 switch (addrs[0].ss_family) { 2137 #ifdef INET6 2138 case AF_INET6: 2139 fin6 = (struct sockaddr_in6 *)&addrs[0]; 2140 lin6 = (struct sockaddr_in6 *)&addrs[1]; 2141 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 2142 lin6->sin6_len != sizeof(struct sockaddr_in6)) 2143 return (EINVAL); 2144 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 2145 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 2146 return (EINVAL); 2147 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 2148 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 2149 fin = (struct sockaddr_in *)&addrs[0]; 2150 lin = (struct sockaddr_in *)&addrs[1]; 2151 break; 2152 } 2153 error = sa6_embedscope(fin6, V_ip6_use_defzone); 2154 if (error) 2155 return (error); 2156 error = sa6_embedscope(lin6, V_ip6_use_defzone); 2157 if (error) 2158 return (error); 2159 break; 2160 #endif 2161 case AF_INET: 2162 fin = (struct sockaddr_in *)&addrs[0]; 2163 lin = (struct sockaddr_in *)&addrs[1]; 2164 if (fin->sin_len != sizeof(struct sockaddr_in) || 2165 lin->sin_len != sizeof(struct sockaddr_in)) 2166 return (EINVAL); 2167 break; 2168 default: 2169 return (EINVAL); 2170 } 2171 INP_INFO_WLOCK(&V_tcbinfo); 2172 switch (addrs[0].ss_family) { 2173 #ifdef INET6 2174 case AF_INET6: 2175 inp = in6_pcblookup_hash(&V_tcbinfo, &fin6->sin6_addr, 2176 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 0, 2177 NULL); 2178 break; 2179 #endif 2180 case AF_INET: 2181 inp = in_pcblookup_hash(&V_tcbinfo, fin->sin_addr, 2182 fin->sin_port, lin->sin_addr, lin->sin_port, 0, NULL); 2183 break; 2184 } 2185 if (inp != NULL) { 2186 INP_WLOCK(inp); 2187 if (inp->inp_flags & INP_TIMEWAIT) { 2188 /* 2189 * XXXRW: There currently exists a state where an 2190 * inpcb is present, but its timewait state has been 2191 * discarded. For now, don't allow dropping of this 2192 * type of inpcb. 2193 */ 2194 tw = intotw(inp); 2195 if (tw != NULL) 2196 tcp_twclose(tw, 0); 2197 else 2198 INP_WUNLOCK(inp); 2199 } else if (!(inp->inp_flags & INP_DROPPED) && 2200 !(inp->inp_socket->so_options & SO_ACCEPTCONN)) { 2201 tp = intotcpcb(inp); 2202 tp = tcp_drop(tp, ECONNABORTED); 2203 if (tp != NULL) 2204 INP_WUNLOCK(inp); 2205 } else 2206 INP_WUNLOCK(inp); 2207 } else 2208 error = ESRCH; 2209 INP_INFO_WUNLOCK(&V_tcbinfo); 2210 return (error); 2211 } 2212 2213 SYSCTL_PROC(_net_inet_tcp, TCPCTL_DROP, drop, 2214 CTLTYPE_STRUCT|CTLFLAG_WR|CTLFLAG_SKIP, NULL, 2215 0, sysctl_drop, "", "Drop TCP connection"); 2216 2217 /* 2218 * Generate a standardized TCP log line for use throughout the 2219 * tcp subsystem. Memory allocation is done with M_NOWAIT to 2220 * allow use in the interrupt context. 2221 * 2222 * NB: The caller MUST free(s, M_TCPLOG) the returned string. 2223 * NB: The function may return NULL if memory allocation failed. 2224 * 2225 * Due to header inclusion and ordering limitations the struct ip 2226 * and ip6_hdr pointers have to be passed as void pointers. 2227 */ 2228 char * 2229 tcp_log_addrs(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 2230 const void *ip6hdr) 2231 { 2232 char *s, *sp; 2233 size_t size; 2234 struct ip *ip; 2235 #ifdef INET6 2236 const struct ip6_hdr *ip6; 2237 2238 ip6 = (const struct ip6_hdr *)ip6hdr; 2239 #endif /* INET6 */ 2240 ip = (struct ip *)ip4hdr; 2241 2242 /* 2243 * The log line looks like this: 2244 * "TCP: [1.2.3.4]:50332 to [1.2.3.4]:80 tcpflags 0x2<SYN>" 2245 */ 2246 size = sizeof("TCP: []:12345 to []:12345 tcpflags 0x2<>") + 2247 sizeof(PRINT_TH_FLAGS) + 1 + 2248 #ifdef INET6 2249 2 * INET6_ADDRSTRLEN; 2250 #else 2251 2 * INET_ADDRSTRLEN; 2252 #endif /* INET6 */ 2253 2254 /* Is logging enabled? */ 2255 if (tcp_log_debug == 0 && tcp_log_in_vain == 0) 2256 return (NULL); 2257 2258 s = malloc(size, M_TCPLOG, M_ZERO|M_NOWAIT); 2259 if (s == NULL) 2260 return (NULL); 2261 2262 strcat(s, "TCP: ["); 2263 sp = s + strlen(s); 2264 2265 if (inc && ((inc->inc_flags & INC_ISIPV6) == 0)) { 2266 inet_ntoa_r(inc->inc_faddr, sp); 2267 sp = s + strlen(s); 2268 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 2269 sp = s + strlen(s); 2270 inet_ntoa_r(inc->inc_laddr, sp); 2271 sp = s + strlen(s); 2272 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 2273 #ifdef INET6 2274 } else if (inc) { 2275 ip6_sprintf(sp, &inc->inc6_faddr); 2276 sp = s + strlen(s); 2277 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 2278 sp = s + strlen(s); 2279 ip6_sprintf(sp, &inc->inc6_laddr); 2280 sp = s + strlen(s); 2281 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 2282 } else if (ip6 && th) { 2283 ip6_sprintf(sp, &ip6->ip6_src); 2284 sp = s + strlen(s); 2285 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 2286 sp = s + strlen(s); 2287 ip6_sprintf(sp, &ip6->ip6_dst); 2288 sp = s + strlen(s); 2289 sprintf(sp, "]:%i", ntohs(th->th_dport)); 2290 #endif /* INET6 */ 2291 } else if (ip && th) { 2292 inet_ntoa_r(ip->ip_src, sp); 2293 sp = s + strlen(s); 2294 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 2295 sp = s + strlen(s); 2296 inet_ntoa_r(ip->ip_dst, sp); 2297 sp = s + strlen(s); 2298 sprintf(sp, "]:%i", ntohs(th->th_dport)); 2299 } else { 2300 free(s, M_TCPLOG); 2301 return (NULL); 2302 } 2303 sp = s + strlen(s); 2304 if (th) 2305 sprintf(sp, " tcpflags 0x%b", th->th_flags, PRINT_TH_FLAGS); 2306 if (*(s + size - 1) != '\0') 2307 panic("%s: string too long", __func__); 2308 return (s); 2309 }
Cache object: b5a2fa9ac1828e7572b911c04ab2b02f
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]